Some catalysts, particularly those comprising a metalated aryl group, polymerize via an unusual mechanism, in which the monomer modifies the ligand framework. An example of this type of catalyst is a pyridyl-amide hafnium complex that has been described in both the open and patent literature. In such cases, the true catalyst identity is determined by the monomer(s) being polymerized. It is desirable to have a catalyst with this modification already in place to decouple the catalyst performance from the monomer makeup, better enabling catalyst optimization.